Take Your Skills to the Next Level With Kotlin.
Kotlin is a modern open-source programming language that suits several development purposes like Server-side, Web-front, Mobile, Data-science and Native programming.
Kotlin also supports multiple VMs(Java VMs and JavaScript VMs) and is used in cross-platform mobile development(Android and iOS).
In this article, I’ll be discussing the advantages of Kotlin in regular server-side programming with the target audience as Java developers.
1. Concise code –> Fewer Bugs
With Kotlin, you can produce beautiful code that is easily readable and concise. It reduces verbosity while retaining clarity.
Below are a few Kotlin features that help code base shrink and increase quality.
i) Type inference:
Like Java, Kotlin is a strongly typed language. But unlike Java, you can omit the explicit data types. The compiler infers the data type of the initializer.
ii) Constructor & method overloading with default arguments:
You can overload constructors and functions by varying parameters.
iii) `when` (switch with Superpowers):
Kotlin replaces switch with when. when offers much more over the regular switch block.
- It can be an expression or a statement.
- The argument is optional.
- The break statement is no more needed.
- It can have complex case conditions.
iv) String interpolation:
No more String concatenation or String formats are needed. Like many other languages, Kotlin supports template expressions in a string.
v) Equality operator redefined:
The equality operator(==) in Kotlin is intuitive and denotes Structural equality(.equals())
For referential equality, you can use ===
vi) Destructuring:
Destructuring unpack values from arrays, or properties from objects, into distinct variables.
vii) Smart casts:
Kotlin doesn’t need explicit cast operation if we have already performed a type check. The Kotlin compiler tracks the is-checks.
viii) data class: (Alternative to Bean class boilerplate code)
Kotlin data classes consist of boilerplate codes for any bean class.
It has getters, setters, toString, hashCode, equals, and copy(custom clone) method.
2. Safe code
With its NULL safety feature, Kotlin provides freedom from the constant fear of NullPointerException. You have to beg to get a NullPointerException. The Kotlin type system distinguishes between usual references and nullable references. You can compare this with Java’s Option class, but with cool moves.
3. Excellent support for functional programming
In Kotlin, functions are first-class citizens. Functions can be assigned to the variables, passed as an argument, or returned from another function. Functions have their own type and are called function type.
The functional programming in Kotlin is intuitive and helps to produce concise code. Often, Java developers find it challenging to adapt to the functional-programming style, but with Kotlin, functional programming’s learning curve is significantly less.
Example of Top-level functions
i) Lambda Expressions:
It’s the shortest way to define a function. No “fun” keyword or function name is required. Also, no need to mention the return keyword. It treats the last statement of the function as the return statement.
ii) Anonymous function:
Anonymous functions are the lengthy form of lambda functions with explicit fun prefix and return statements. It is idiomatic when the function contains multiple return statements.
iii) Higher-Order function:
A higher-order function is a function that takes a function as an argument or returns a function.
iv) Extension function:
Extension function provides the ability to add more functionality to the existing classes without inheriting them.
Some example of extension functions in Kotlin stdlib are:
let, run, apply, also, takeIf, and takeUnless.
4. Speeds up every-day developmental tasks
i) Excellent IDE support:
Kotlin belongs to JetBrains. So the popular IDE “Intellij IDEA” has excellent support for Kotlin. JetBrains sees a lot of java code, and they understand the pain points of the Java developers. The IDE guides you through tips to write better code and to avoid general mistakes.
While copy-pasting Java code, the IDE automatically converts them to Kotlin for you.
ii) Useful functions in existing Java interfaces:
Kotlin provides a lot of valuable functions on top of existing popular java classes like Collections, Files, String, Wrapper Classes, etc. These help to reduce boilerplate code.
iii) Other useful functionalities:
Kotlin offers a myriad of handy features that facilitate every-day development tasks compared to Java.
e.g., Default Arguments, Named Arguments, Properties, Operator Overloading, Ranges, Destructuring Declarations, Companion objects(simpler Singleton), Asynchronous programming, fail-fast compiler(avoids runtime errors), etc.
5. Interoperable with Java
Kotlin is 100% interoperable with Java. You can call Java code from Kotlin and vice-versa seamlessly, as it generates the same byte code. So you no need to wait for a new project to use Kotlin. You can start right away using Kotlin in your existing project and existing Java code.
You don’t have to do any radical change to write in Kotlin in your existing Java project; add the kotlin-maven-plugin as your build plugin, and you are all set to use Kotlin.
Conclusion
Kotlin is an enterprise language and has been around for a few years. Kotlin doesn’t come from an academic or research background. It was built with the enterprise in mind to solve practical, real-world development problems. The language is intuitive and easy to understand. The interoperability with Java makes it friendly to use in any Java project with zero risks.
The transition from Java to Kotlin is straightforward. It closely resembles what you already know. It opens up a new world of possibilities for you to be creative and to solve the same problems in a very different way.
